Solid golf ball

Abstract

A solid golf ball comprising a solid core and a cover has a multiplicity of dimples in its surface. The core undergoes a distortion of 2.8-4.0 mm under a load of 100 kg. The distortion (mm) of the core under a load of 100 kg divided by the distortion (mm) of the ball under a load of 100 kg is 1.0-1.3. The cover has a gage of 1.4-1.9 mm and a Shore D hardness of 53-60. Dimples of at least three types having different diameters are formed in the cover surface in a total number of 390-450. The diameter/depth ratio of each dimple is from 18/1 to 27/1. The volume of a dimple divided by the volume of a cylinder whose diameter and height correspond to the diameter and depth of the dimple, respectively, is 0.390-0.550. The golf ball is improved in flight distance, hitting feel and spin and will cover a distance even when hit at low head speeds.

We claim: 
     
       1. A solid golf ball comprising; a solid core and a cover enclosing the core and having a multiplicity of dimples in its surface, wherein the core undergoes a distortion in the range of 2.8 to 4.0 mm under a load of 100 kg, the distortion (mm) of the core under a load of 100 kg divided by the distortion (mm) of the ball under a load of 100 kg is in the range of 1.0 to 1.3,   the cover has a gage in the range of 1.4 to 1.9 mm and a Shore D hardness of 53 to 60,   the dimples are of at least three type shaving different diameters, the diameter (mm) divided by the depth (mm) of each dimple is from 18 to 27, the volume of a dimple divided by the volume of a cylinder whose diameter and height correspond to the diameter and depth of the dimple, V 0  respectively, is from 0.390 to 0.550, the dimples having the largest diameter have a diameter of 3.6 to 4.5 mm and the dimples having the smallest diameter have a diameter of 2.0 to 3.8 mm and the total number of dimples is in the range of 390 to 450.   
     
     
       2. The solid golf ball of claim 1 wherein those dimples having the largest diameter account for at least 10% of the entire dimples, and the ratio of the diameter (mm) to the depth (mm) of said dimples having the largest diameter is from 22/1 to 26/1. 
     
     
       3. The solid golf ball of claim 1, wherein said core has a distortion in the range of 3.0 to 4.0 mm under a load of 100 kg. 
     
     
       4. The solid golf ball of claim 1, wherein said cover has a thickness in the range of 1.4 to 1.8 mm. 
     
     
       5. The solid golf ball of claim 1, wherein said solid core has a diameter in the range of 38.85 to 39.95 mm. 
     
     
       6. The solid golf ball of claim 1, wherein said dimples comprise 3 to 5 different types. 
     
     
       7. The solid golf ball of claim 1, wherein said dimples have a diameter in the range of 3.0 to 4.3 m and a depth in the range of 0.09 to 0.25 mm. 
     
     
       8. The solid golf ball of claim 1, wherein V 0  is in the range of 0.395 to 0.545.